package com.wfcm.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5 {
	public final static String md5(String source) {
		String dest = null;
		try {
			MessageDigest md5 = MessageDigest.getInstance("MD5");
			char[] charArray = source.toCharArray();
			byte[] byteArray = new byte[charArray.length];
			for (int i = 0; i < charArray.length; i++)
				byteArray[i] = (byte) charArray[i];
			byte[] md5Bytes = md5.digest(byteArray);
			StringBuffer hexValue = new StringBuffer();
			for (int i = 0; i < md5Bytes.length; i++) {
				int val = ((int) md5Bytes[i]) & 0xff;
				if (val < 16)
					hexValue.append("0");
				hexValue.append(Integer.toHexString(val));
			}
			dest = hexValue.toString();

		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
		return dest;
	}
//	public static void main(String[] args) {
//		String s = "111111";
//		//e10adc3949ba59abbe56e057f20f883e
//		System.out.println(MD5.md5(MD5.md5(s)));
//	}
	
	public final static String md5(byte[]  btInput) {
		char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
		try {
			// 获得MD5摘要算法的MessageDigest 对象
			MessageDigest mdInst = MessageDigest.getInstance("MD5");
			// 使用指定的字节更新摘要
			mdInst.update(btInput);
			// 获得密文
			byte[] md = mdInst.digest();
			// 把密文转换成十六进制的字符串形式
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++) {
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}
	
	
	
}
